Having problems with your 1999 Chevrolet Blazer ?
Heater doesnt blow hot air,,have replaced thermostat
What your going to have to do is back flush the heater core.After that flush the cooling system out.Prestone makes a real good flush kit that works really good.This will get you through for a while.But eventually you will have to replace the heater core.Which is not a fun job because the whole dash panel has to be removed to get to the hvac module assembly and heater core.Hope this helps.Good luck.
Have you checked to make sure your antifreeze is up to the correct level? If fluid is low, it won't heat. Let the engine run with the radiator cap off in case you have an air pocket in cooling system.
Repair Help & Product Troubleshooting for 1999 Chevrolet Blazer
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